1096. Effect of Diarrheal Illness During Pregnancy on Adverse Birth Outcomes in Nepal

Abstract Background Adverse birth outcomes, including low birthweight (LBW), small-for-gestational-age (SGA) and preterm birth, contribute to 60–80% of infant mortality worldwide. Little published data exist on the association between diarrhea during pregnancy and adverse birth outcomes. We sought to identify whether diarrhea during pregnancy was associated with adverse birth outcomes. Methods We used data from a community-based, prospective randomized trial of maternal influenza immunization of pregnant women and their infants conducted in rural Nepal from 2011 to 2014. Illness episodes were defined as at least three watery bowel movements per day for one or more days with 7 diarrhea-free days between episodes. Diarrheal illnesses were identified through longitudinal household-based weekly symptom surveillance. The c2 test, two-sample t-test, and log-binomial regression were performed to evaluate baseline characteristics and the association between diarrhea during pregnancy and adverse birth outcomes. Results Of 3,682 women in the study, 527 (14.3%) experienced one or more episodes of diarrhea during pregnancy. Diarrhea incidence was not seasonal. Women with diarrhea had a median of one episode of diarrhea (interquartile range (IQR) 1–2 episodes) and two cumulative days of diarrhea (IQR 1–3 days). Of women with diarrhea, 16.1% (85) sought medical care. Mean maternal age, parity, biomass cook stove use, home latrine, water source, caste, and smoking did not differ in pregnant women with and without diarrhea. In crude and adjusted analyses, women with diarrhea during pregnancy were significantly more likely to have SGA infants (42.6% vs. 36.8%; adjusted risk ratio=1.20, 95% CI 1.06–1.36, P = 0.005). LBW and preterm birth incidence did not significantly differ between women with diarrhea during pregnancy and those without. There was no significant association between seeking medical care for diarrhea and birth outcomes. Conclusion Diarrheal illness during pregnancy was associated with a significantly higher risk of SGA infants in this rural South Asian population. Interventions to reduce the burden of diarrheal illness during pregnancy may have an impact on SGA births in resource-limited settings. Disclosures All authors: No reported disclosures.

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Effect of Diarrheal Illness During Pregnancy on Adverse Birth Outcomes in Nepal

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz011 ◽

2019 ◽

Vol 6 (2) ◽

Author(s):

Kira L Newman ◽

Kathryn Gustafson ◽

Janet A Englund ◽

Amalia Magaret ◽

Subarna Khatry ◽

...

Keyword(s):

Preterm Birth ◽

Birth Outcomes ◽

Low Birthweight ◽

Asian Population ◽

Published Data ◽

Adverse Birth Outcomes ◽

South Asian Population ◽

Adjusted Risk ◽

Diarrheal Illness ◽

Bowel Movements

Abstract Background Adverse birth outcomes, including low birthweight, small for gestational age (SGA), and preterm birth, contribute to 60%–80% of infant mortality worldwide. Little published data exist on the association between diarrhea during pregnancy and adverse birth outcomes. Methods Data were used from 2 community-based, prospective randomized trials of maternal influenza immunization during pregnancy conducted in rural Nepal from 2011 to 2014. Diarrheal illnesses were identified through longitudinal household-based weekly symptom surveillance. Diarrhea episodes were defined as at least 3 watery bowel movements per day for 1 or more days with 7 diarrhea-free days between episodes. The Poisson and log-binomial regression were performed to evaluate baseline characteristics and association between diarrhea during pregnancy and adverse birth outcomes. Results A total of 527 of 3693 women in the study (14.3%) experienced diarrhea during pregnancy. Women with diarrhea had a median of 1 episode of diarrhea (interquartile range [IQR], 1–2 episodes) and 2 cumulative days of diarrhea (IQR, 1–3 days). Of women with diarrhea, 85 (16.1%) sought medical care. In crude and adjusted analyses, women with diarrhea during pregnancy were more likely to have SGA infants (42.6% vs 36.8%; adjusted risk ratio = 1.20; 95% confidence interval, 1.06–1.36; P = .005). Birthweight and preterm birth incidence did not substantially differ between women with diarrhea during pregnancy and those without. Conclusions Diarrheal illness during pregnancy was associated with a higher risk of SGA infants in this rural South Asian population. Interventions to reduce the burden of diarrheal illness during pregnancy may have an impact on SGA births in resource-limited settings.

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Interventions to improve birth outcomes of pregnant women living in low- and middle-income countries: a systematic review and network meta-analysis

Gates Open Research ◽

10.12688/gatesopenres.13081.2 ◽

2020 ◽

Vol 3 ◽

pp. 1657

Author(s):

Jay J. H. Park ◽

Ofir Harari ◽

Ellie Siden ◽

Michael Zoratti ◽

Louis Dron ◽

...

Keyword(s):

Clinical Trials ◽

Preterm Birth ◽

Pregnant Women ◽

Birth Outcomes ◽

Low Birthweight ◽

Meta Analysis ◽

Standard Of Care ◽

Adverse Birth Outcomes ◽

Middle Income ◽

Middle Income Countries

Background: Improving the health of pregnant women is important to prevent adverse birth outcomes, such as preterm birth and low birthweight. We evaluated the comparative effectiveness of interventions under the domains of micronutrient, balanced energy protein, deworming, maternal education, and water sanitation and hygiene (WASH) for their effects on these adverse birth outcomes. Methods: For this network meta-analysis, we searched for randomized clinical trials (RCTs) of interventions provided to pregnant women in low- and middle-income countries (LMICs). We searched for reports published until September 17, 2019 and hand-searched bibliographies of existing reviews. We extracted data from eligible studies for study characteristics, interventions, participants’ characteristics at baseline, and birth outcomes. We compared effects on preterm birth (<37 gestational week), low birthweight (LBW; <2500 g), and birthweight (continuous) using studies conducted in LMICs. Results: Our network meta-analyses were based on 101 RCTs (132 papers) pertaining to 206,531 participants. Several micronutrients and balanced energy food supplement interventions demonstrated effectiveness over standard-of-care. For instance, versus standard-of-care, micronutrient supplements for pregnant women, such as iron and calcium, decreased risks of preterm birth (iron: RR=0.70, 95% credible interval [Crl] 0.47, 1.01; calcium: RR=0.76, 95%Crl 0.56, 0.99). Daily intake of 1500kcal of local food decreased the risks of preterm birth (RR=0.36, 95%Crl 0.16, 0.77) and LBW (RR=0.17, 95%Crl 0.09, 0.29), respectively when compared to standard-of-care. Educational and deworming interventions did not show improvements in birth outcomes, and no WASH intervention trials reported on these adverse birth outcomes. Conclusion: We found several pregnancy interventions that improve birth outcomes. However, most clinical trials have only evaluated interventions under a single domain (e.g. micronutrients) even though the causes of adverse birth outcomes are multi-faceted. There is a need to combine interventions that of different domains as packages and test for their effectiveness. Registration: PROSPERO CRD42018110446; registered on 17 October 2018.

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Interventions to improve birth outcomes of pregnant women living in low- and middle-income countries: a systematic review and network meta-analysis

Gates Open Research ◽

10.12688/gatesopenres.13081.1 ◽

2019 ◽

Vol 3 ◽

pp. 1657 ◽

Cited By ~ 2

Author(s):

Jay J. H. Park ◽

Ofir Harari ◽

Ellie Siden ◽

Michael Zoratti ◽

Louis Dron ◽

...

Keyword(s):

Clinical Trials ◽

Preterm Birth ◽

Pregnant Women ◽

Birth Outcomes ◽

Low Birthweight ◽

Meta Analysis ◽

Standard Of Care ◽

Adverse Birth Outcomes ◽

Middle Income ◽

Middle Income Countries

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Influence of Prenatal Exposure to Mercury, Perceived Stress, and Depression on Birth Outcomes in Suriname: Results from the MeKiTamara Study

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17124444 ◽

2020 ◽

Vol 17 (12) ◽

pp. 4444

Author(s):

Anisma R. Gokoel ◽

Wilco C. W. R. Zijlmans ◽

Hannah H. Covert ◽

Firoz Abdoel Wahid ◽

Arti Shankar ◽

...

Keyword(s):

Preterm Birth ◽

Birth Outcomes ◽

Prenatal Exposure ◽

Perceived Stress ◽

Apgar Score ◽

Low Birthweight ◽

Depression Scale ◽

Study Cohort ◽

Adverse Birth Outcomes ◽

Probable Depression

Prenatal exposure to mercury, stress, and depression may have adverse effects on birth outcomes. Little is known on the influence of chemical and non-chemical stressors on birth outcomes in the country of Suriname. We assessed the influence of prenatal exposure to mercury, perceived stress, and depression on adverse birth outcomes in 1143 pregnant Surinamese women who participated in the Caribbean Consortium for Research in Environmental and Occupational Health-MeKiTamara prospective cohort study. Associations between mercury (≥1.1 μg/g hair, USEPA action level/top versus bottom quartile), probable depression (Edinburgh Depression Scale ≥12), high perceived stress (Cohen’s Perceived Stress Scale ≥20), and adverse birth outcomes (low birthweight (<2500 g), preterm birth (<37 completed weeks of gestation), and low Apgar score (<7 at 5 min)) were assessed using bivariate and multivariate logistic regressions. Prevalence of elevated mercury levels, high perceived stress, and probable depression were 37.5%, 27.2%, and 22.4%, respectively. Mercury exposure was significantly associated with preterm birth in the overall study cohort (OR 2.47; 95% CI 1.05–5.83) and perceived stress with a low Apgar score (OR 9.73; 95% CI 2.03–46.70). Depression was not associated with any birth outcomes. These findings can inform policy- and practice-oriented solutions to improve maternal and child health in Suriname.

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A Swedish Population-based Study of Adverse Birth Outcomes among Pregnant Women Treated with Buprenorphine or Methadone: Preliminary Findings

Substance Abuse Research and Treatment ◽

10.4137/sart.s38887 ◽

2016 ◽

Vol 10 ◽

pp. SART.S38887

Author(s):

Keele E. Wurst ◽

Barbara K. Zedler ◽

Andrew R. Joyce ◽

Maciek Sasinowski ◽

E. Lenn Murrelle

Keyword(s):

Preterm Birth ◽

General Population ◽

Pregnant Women ◽

Birth Outcomes ◽

Congenital Malformations ◽

Mode Of Delivery ◽

Neonatal Abstinence Syndrome ◽

Adverse Birth Outcomes ◽

Abstinence Syndrome ◽

Opioid Agonist

Background Untreated opioid dependence in pregnant women is associated with adverse birth outcomes. Buprenorphine and methadone are options for opioid agonist medication-assisted treatment during pregnancy. Objective The aim of this study was to describe adverse birth outcomes observed with buprenorphine or methadone treatment compared to the general population in Sweden. Methods Pregnant women and their corresponding births during 2005–2011 were identified in the Swedish Medical Birth Register. Data on stillbirth, neonatal/infant death, mode of delivery, gestational age at birth, Apgar score, growth outcomes, neonatal abstinence syndrome, and congenital malformations were examined. Frequencies were compared using two-sided Fisher's exact tests. Unadjusted estimates of birth outcomes for women treated with buprenorphine or methadone were compared to the registered general population. Results A total of 746,257 pregnancies among 538,178 unique women resulted in 746,485 live births. Among the 194 women treated with buprenorphine ( N = 176) or methadone ( N = 52), no stillbirths or neonatal/infant deaths occurred. Neonatal abstinence syndrome developed in 23.3% and 38.5% of infants born to mothers treated with buprenorphine and methadone, respectively. The frequency of the selected adverse birth outcomes assessed in women treated with buprenorphine as compared to the general population was not significantly different. However, a significantly higher frequency of preterm birth and congenital malformations was observed in women treated with methadone as compared to the general population. Compared with the general population, methadone-treated women were significantly older than buprenorphine-treated women, and both treatment groups began prenatal care later, were more likely to smoke cigarettes, and did not cohabitate with the baby's father. Conclusions An increased frequency of the selected adverse birth outcomes was not observed with buprenorphine treatment during pregnancy. Twofold increased frequency of preterm birth [2.21 (1.11, 4,41)] and congenital malformations [2.05 (1.08, 3.87)] was observed in the methadone group, which may be partly explained by older average maternal age and differences in other measured and unmeasured confounders.

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Estimating the risk of adverse birth outcomes in pregnant women undergoing non-obstetric surgery using routinely collected NHS data: an observational study

Health Services and Delivery Research ◽

10.3310/hsdr04290 ◽

2016 ◽

Vol 4 (29) ◽

pp. 1-76 ◽

Cited By ~ 3

Author(s):

Paul Aylin ◽

Phillip Bennett ◽

Alex Bottle ◽

Stephen Brett ◽

Vinnie Sodhi ◽

...

Keyword(s):

Observational Study ◽

Pregnant Women ◽

Spontaneous Abortion ◽

Birth Outcomes ◽

Low Birthweight ◽

Attributable Risk ◽

Adverse Birth Outcomes ◽

Inpatient Stay ◽

Underlying Condition ◽

Obstetric Surgery

BackgroundPrevious research suggests that non-obstetric surgery is carried out in 1–2% of all pregnancies. However, there is limited evidence quantifying the associated risks. Furthermore, of the evidence available, none relates directly to outcomes in the UK, and there are no current NHS guidelines regarding non-obstetric surgery in pregnant women.ObjectivesTo estimate the risk of adverse birth outcomes of pregnancies in which non-obstetric surgery was or was not carried out. To further analyse common procedure groups.Data SourceHospital Episode Statistics (HES) maternity data collected between 2002–3 and 2011–12.Main outcomesSpontaneous abortion, preterm delivery, maternal death, caesarean delivery, long inpatient stay, stillbirth and low birthweight.MethodsWe utilised HES, an administrative database that includes records of all patient admissions and day cases in all English NHS hospitals. We analysed HES maternity data collected between 2002–3 and 2011–12, and identified pregnancies in which non-obstetric surgery was carried out. We used logistic regression models to determine the adjusted relative risk and attributable risk of non-obstetric surgical procedures for adverse birth outcomes and the number needed to harm.ResultsWe identified 6,486,280 pregnancies, in 47,628 of which non-obstetric surgery was carried out. In comparison with pregnancies in which surgery was not carried out, we found that non-obstetric surgery was associated with a higher risk of adverse birth outcomes, although the attributable risk was generally low. We estimated that for every 287 pregnancies in which a surgical operation was carried out there was one additional stillbirth; for every 31 operations there was one additional preterm delivery; for every 25 operations there was one additional caesarean section; for every 50 operations there was one additional long inpatient stay; and for every 39 operations there was one additional low-birthweight baby.LimitationsWe have no means of disentangling the effect of the surgery from the effect of the underlying condition itself. Many spontaneous abortions will not be associated with a hospital admission and, therefore, will not be included in our analysis. A spontaneous abortion may be more likely to be reported if it occurs during the same hospital admission as the procedure, and this could account for the associated increased risk with surgery during pregnancy. There are missing values of key data items to determine parity, gestational age, birthweight and stillbirth.ConclusionsThis is the first study to report the risk of adverse birth outcomes following non-obstetric surgery during pregnancy across NHS hospitals in England. We have no means of disentangling the effect of the surgery from the effect of the underlying condition itself. Our observational study can never attribute a causal relationship between surgery and adverse birth outcomes, and we were unable to determine the risk of not undergoing surgery where surgery was clinically indicated. We have some reservations over associations of risk factors with spontaneous abortion because of potential ascertainment bias. However, we believe that our findings and, in particular, the numbers needed to harm improve on previous research, utilise a more recent and larger data set based on UK practices, and are useful reference points for any discussion of risk with prospective patients. The risk of adverse birth outcomes in pregnant women undergoing non-obstetric surgery is relatively low, confirming that surgical procedures during pregnancy are generally safe.Future workFurther evaluation of the association of non-obstetric surgery and spontaneous abortion. Evaluation of the impact of non-obstetric surgery on the newborn (e.g. neonatal intensive care unit admission, prolonged length of neonatal stay, neonatal death).FundingThe National Institute for Health Research Health Services and Delivery Research programme.

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Adverse birth outcomes and associated factors among mothers who delivered in Bale zone hospitals, Oromia Region, Southeast Ethiopia

Journal of International Medical Research ◽

10.1177/03000605211013209 ◽

2021 ◽

Vol 49 (5) ◽

pp. 030006052110132

Author(s):

Sisay Degno ◽

Bikila Lencha ◽

Ramato Aman ◽

Daniel Atlaw ◽

Ashenafi Mekonnen ◽

...

Keyword(s):

Preterm Birth ◽

Antenatal Care ◽

Birth Outcomes ◽

Associated Factors ◽

Low Birthweight ◽

Multiple Pregnancy ◽

Bivariate Analysis ◽

Adverse Birth Outcomes ◽

Southeast Ethiopia ◽

Bale Zone

Objective Adverse birth outcomes, which include stillbirth, preterm birth, low birthweight, congenital abnormalities, and stillbirth, are the leading cause of neonatal and infant mortality worldwide. We assessed adverse birth outcomes and associated factors among mothers who gave birth in Bale zone hospitals, Oromia, Southeast Ethiopia. Methods We used systematic random sampling in this cross-sectional study. We identified factors associated with adverse birth outcomes using bivariate analysis and multivariable logistic regression analysis. Results The proportion of adverse birth outcomes among participants was 21%. Of 576 births, 70 (12.2%) were low birthweight, 49 (8.5%) were preterm birth, 45 (7.8%) were stillbirth, and 18 (3.1%) infants had congenital anomalies. Inadequate antenatal care (adjusted odds ratio [AOR] = 6.58, 95% confidence interval [CI] 3.25–13.32), multiple pregnancy (AOR = 4.74, 95% CI 1.55–14.45), premature rupture of membranes in the current pregnancy (AOR = 2.31, 95% CI 1.26–4.21), hemoglobin level < 11 g/dL (AOR = 3.22, 95% CI 1.85–5.58), and mid-upper arm circumference less than 23 cm (AOR = 5.93, 95% CI 3.49–10.08) were all significantly associated with adverse birth outcomes. Conclusions Approximately one in five study participants had adverse birth outcomes. Increasing antenatal care uptake, ferrous supplementation during pregnancy, and improving the quality of maternal health services are recommended.

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Electronic cigarettes may not be a “safer alternative” of conventional cigarettes during pregnancy: evidence from the nationally representative PRAMS data

BMC Pregnancy and Childbirth ◽

10.1186/s12884-020-03247-6 ◽

2020 ◽

Vol 20 (1) ◽

Cited By ~ 1

Author(s):

Sooyong Kim ◽

Sanda Cristina Oancea

Keyword(s):

Pregnant Women ◽

Birth Outcomes ◽

Low Birthweight ◽

Electronic Cigarettes ◽

Adverse Outcomes ◽

Adverse Birth Outcomes ◽

Third Trimester ◽

Pregnancy Risk ◽

The Third ◽

Shared Risk

Abstract Background Conventional cigarette (CC) smoking is one of the most preventable causes of adverse birth outcomes. Although electronic cigarettes (ECs) are considered to be safer than CCs during pregnancy, the evidence is yet to be presented. This study examines the effects of prenatal EC use on neonatal birth outcomes compared to those of CC smokers and complete tobacco abstainers. Methods Data was extracted from 55,251 pregnant women who participated in the Phase 8 survey of the Pregnancy Risk Assessment Monitoring System between 2016 and 2018. Participants were classified into three groups based on their smoking behaviors in the third trimester: complete tobacco abstinence, exclusive CC smoking, or exclusive EC use. Adverse outcomes included infants being small-for-gestational-age (SGA), having low birthweight (LBW), and being born at preterm. EC users were matched to complete abstainers and CC smokers who share the same baseline characteristics in race/ethnicity, age, educational attainment, income, prenatal care adequacy, and first- and second-trimester CC smoking statuses. The association between EC use and adverse birth outcomes were examined by survey-weighted logistic regression analyses in the matched population. Results Among participants, 1.0% of women reported having used ECs during the third trimester, 60% of which reported using ECs exclusively. Neonates of EC users were significantly more likely to be SGA (OR 1.76; 95% CI 1.04, 2.96), have LBW (OR 1.53; 95% CI 1.06, 2.22), or be born preterm (OR 1.86; 95% CI 1.11, 3.12) compared to tobacco abstainers. However, odds of EC users’ pregnancies resulting in SGA (OR 0.67; 95% CI 0.30, 1.47), LBW (OR 0.71; 95% CI 0.37, 1.37), or preterm birth (OR 1.06; 95% CI 0.46, 2.48) were not significantly lower than those of CC smokers. Conclusions Even after accounting for shared risk factors between prenatal tobacco use and adverse birth outcomes, EC use remains an independent risk factor for neonatal complications and is not a safer alternative to CC smoking during pregnancy. Until further research is completed, all pregnant women are encouraged to abstain from all tobacco products including ECs.

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Prenatal Exposure to Ambient Pesticides and Adverse Birth Outcomes in Agricultural Regions of California

10.20944/preprints201806.0388.v1 ◽

2018 ◽

Author(s):

Chenxiao Ling ◽

Zeyan Liew ◽

Ondine S. von Ehrenstein ◽

Julia E. Heck ◽

Andrew S. Park ◽

...

Keyword(s):

Preterm Birth ◽

Birth Outcomes ◽

Prenatal Exposure ◽

Low Birthweight ◽

Female Offspring ◽

Adverse Birth Outcomes ◽

Second Trimester ◽

Agricultural Pesticides ◽

Term Births ◽

Birth Records

Findings from studies of prenatal exposure to pesticides and adverse birth outcomes have been equivocal so far. We examined prenatal exposure to agricultural pesticides in relation to preterm birth and term low birthweight, respectively, in children born between 1998 and 2010 randomly selected from California birth records. We estimated residential exposures to agriculturally applied pesticides within 2 km of residential addresses at birth by pregnancy trimester for 17 individual pesticides and 3 chemical classes (organophosphates, pyrethroids, and carbamates). Among maternal addresses located within 2 km of any agricultural pesticide application, we identified 24,693 preterm and 220,297 term births, and 4,412 term low birthweight and 194,732 term normal birthweight infants. First or second trimester exposures to individual pesticides (e.g., glyphosates, paraquat, imidacloprid) or exposures to 2+ pesticides in the three chemical classes were associated with small increases (3-7%) in risk for preterm birth; associations were stronger for female offspring. We did not find associations between term low birthweight and exposures to pesticides other than for myclobutanil (OR: 1.11; 95% CI: 1.04-1.20) and possibly pyrethroids as a class. Our improved exposure assessment revealed that first and second trimester exposures to pesticides were associated with preterm delivery but few affected term low birthweight.

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Exploring airshed and watershed exposure pathways as mediators of the association between proximity to surface mining and adverse birth outcomes in Central Appalachia

10.21203/rs.3.rs-948330/v1 ◽

2021 ◽

Author(s):

Corrine Warren Ruktanonchai ◽

Molly Xi McKnight ◽

Lauren Grace Buttling ◽

Korine N Kolivras ◽

Leigh-Anne Krometis ◽

...

Keyword(s):

Preterm Birth ◽

Birth Outcomes ◽

Low Birthweight ◽

Surface Mining ◽

Active Surface ◽

Adverse Birth Outcomes ◽

Mining Activities ◽

Potential Exposure ◽

Exposure Pathways ◽

Central Appalachia

Abstract Background Previous work has determined an association between proximity to active surface mining in coal producing counties within Central Appalachia and an increased risk of preterm birth (PTB) and low birthweight (LBW); however, the relative importance of specific exposure pathways explaining this association remains poorly understood. Multiple potential exposure pathways to surface mining activities exist during gestation, including inhalation of particulate matter (airshed exposure), or via exposure to impacted surface waters (watershed exposure). Here, we perform a mediation analysis to explore these pathways and the odds of adverse birth outcomes. Methods We obtained birth records acquired through health departments in WV, KY, VA and TN between 1990 and 2015. Surface mine extents for each year were identified through remotely sensed Landsat imagery. Corresponding airsheds were estimated using the HYSPLIT4 atmospheric trajectory model, while watersheds were assigned using United States Geological Survey’s Watershed Boundary Dataset boundaries. We performed logistic regression to determine associations between exposure and the odds of preterm birth, low birthweight, and term low birthweight, and iteratively included within our models: a) the percent of active surface mining landcover within a 5 km buffer of maternal residence; b) the cumulative potential exposure to air pollutants via the airshed experienced at the maternal residence, and; c) the percent of land experiencing surface mining within the watershed of residency. Results Our baseline models found that active surface mining was associated with an increased odds of PTB (1.09, 1.05 – 1.13) and LBW (1.06, 1.02 – 1.11), while controlling for significant predictors. When mediators were added to the base model, the association between active mining and birth outcomes was reduced (PTB: 1.04, 0.99 – 1.09; LBW 1.04, 0.99 – 1.10), while the odds of PTB and LBW increased with airshed exposure (PTB: 1.14, 1.11 – 1.18; LBW: 1.06, 1.03 – 1.10). Conclusions Results were consistent with a hypothesis of mediation via airshed, but suggested mediation via watershed was less likely. These results suggest that air pollution resulting from surface mining activities may be the primary exposure pathway explaining the association between maternal residence proximity to active surface mining and PTB and LBW.

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